---
title: observedModels
framework: swiftdata
role: symbol
role_heading: Instance Property
path: swiftdata/historyobserver/observedmodels
---

# observedModels

The model types that the observer filters for when evaluating history transactions.

## Declaration

```swift
final let observedModels: [any PersistentModel.Type]
```

## Discussion

Discussion When non-empty, the observer only reports changes whose transactions contain modifications to instances of these types. When empty, the observer treats any new transaction as relevant.

## See Also

### Accessing observer properties

- [eventCounter](swiftdata/historyobserver/eventcounter.md)
- [modelContainer](swiftdata/historyobserver/modelcontainer.md)
- [authors](swiftdata/historyobserver/authors.md)